Revolutionary advances in the technology of avionics sensors have led to many new ways of employing those sensors. One of the most important is the ability to timeshare many avionics functions using shared aperatures and agile beam techniques.One of the critical radar functions is the collection of data to form high and ultra-high resolution synthetic aperture radar (SAR) and inverse SAR (ISAR) imagery. This function may require several tens of seconds to complete under some conditions. The aircraft often cannot devote an uninterrupted period of time of that magnitude to a single function. Technolo9gy Service Corporation (TSC) in cooperation with Hughes Aircraft Company (HAC) proposes to apply modern linear interpolfation/spectral analysis techniques to accommodate missing data. In addition, TSC/HAC propose two major enhancements. One is the fusion of the linear interpolation and autofocus algorithms since both operate on the same set of data. The second is to extend autofocus to the down range dimension. Successful demonstrationj of these methods will result in high-quality imagery and very efficient use of signal processor resources.